In a cellular network, such as one employing orthogonal frequency division multiple access (OFDMA), each cell employs a base station that communicates with user equipment, such as a cell phone, a laptop, or a PDA, that is actively located within its cell. When the user equipment is first turned on, it has to do an initial cell search in order to be connected to the cellular network. This involves a downlink synchronization process between the base station and the user equipment wherein the base station sends a synchronization signal to the user equipment.
During initial cell search, the user equipment establishes timing and frequency offset parameters. Timing involves knowing where to sample the start of the synchronization frame and associated symbols. Frequency offset involves determining the mismatch between the controlling oscillator at the base station and the local oscillator in the user equipment. As the moving user equipment approaches a cell boundary between two adjoining cells, it performs a neighboring cell search in preparation to handover its activation from the initial cell to the neighboring cell. During this time, it receives information from the two base stations. Improvements in the process of transitioning between adjoining cells would prove beneficial in the art.